1. Field of the Invention
This invention relates to modified carbon products and inks and coatings which contain modified carbon products.
2. Discussion of the Related Art
Presently, predominant black pigments are carbon blacks such as furnace blacks which can be used as colorants either in dry, powdered form, a flushed paste, or liquid concentrate form. Generally, the form of the colorant influences the hue, permanency, bulk, opacity, gloss, rheology, end use, and print quality.
There are various classifications of inks used presently. These categories include printing inks, ultraviolet cure inks, ball-point inks, and stamp pad or marking inks. Generally, inks can be applied by letter press, lithographic, flexographic, gravure, silk screen, stencil, duplicating, and electrostatic. Inks thus can be found in such end uses as news, publication, commercial, folding carton, book, corrugated box, paper bag, wrapper, label, metal container, plastic container, plastic film, foil, laminating, food insert, sanitary paper, textile and the like. McGraw-Hill's Encyclopedia of Science and Technology, Vol. 7, pgs. 159-164, provides further details of the types of inks available and their uses, all of which is incorporated herein by reference.
Coatings can contain pigments as well and are used for decorative, protective, and functional treatments of many kinds of surfaces. These surfaces include, coils, metals, appliances, furniture, hardboard, lumber and plywood, marine, maintenance, automobile, cans, and paperboard. Some coatings, such as those on undersea pipelines, are for protective purposes. Others, such as exterior automobile coatings, fulfill both decorative and protective functions. Still others provide friction control on boat decks or car seats. Some coatings control the fouling of ship bottoms, others protect food and beverages in cans. Silicon chips, printed circuit panels, coatings on waveguide fibers for signal transmission, and magnetic coatings on video tapes and computer disks are among many so-called hi-tech applications for coatings.
Categories of aqueous vehicles for aqueous inks and coatings include those in which the binder is soluble in water, those in which it is colloidally dispersed, and those in which it is emulsified to form a latex. The combination of binder and volatile liquid is called the vehicle which may be a solution or a dispersion of fine binder particles in a non-solvent. Pigments are finely divided, insoluble, solid particles dispersed in the coating vehicle and distributed throughtout the binder in the final film. Surfactants can be used as pigment dispersants. The components and manufacturing of aqueous coatings are further discussed in the Concised Encyclopedia of Polymers, Science and Engineering, pgs. 160-171 (1990), which is incorporated herein by reference.
Non-aqueous inks and coatings are used for many applications in which aqueous vehicles are not suitable. For instance, inks which are to be printed on hydrophobic, non-porous substrates such as metal, glass, or plastics must be fast-drying. Therefore, solvents such as ketones, esters, alcohols, or hydrocarbons are often used instead of water. Such solvent-based inks are used widely for printing on paper substrates and industrial labeling of cardboard boxes and various metal or plastic containers and components. Specific examples include news ink compositions and web off-set gloss heat-set ink compositions.
Inks and coatings are also required to be water resistant in certain situations. In such instances, water-resistant resins can be dissolved in non-aqueous solvents of ink and coating formulations to provide the desired water resistance upon drying. A primary use of such non-aqueous coatings is on metal and plastic automotive parts.